Try these people at
Flight Data Systems they might be able to help.
QAR's have come a long way in recent times.
BAE Systems use a CQAR (Card Quick Access Recorder) on helicopters fitted with their HUMS. Typically 32 Mb cards are used for 30 hours flying at standard data rates.
It depends on how much money you want to spend really.
If you are stuck for some more reading try and see this
HOMP site and see what the data gets up to.